Voiding disfunction has been associated with pelvic organ prolapse (POP) in the anterior, apical and posterior compartments. Urethral distortion due to a large cystocele is a plausible mechanism for the anterior compartment. Obstruction secondary to bulge pressure can be the mechanism for apical and posterior, however the influence of these compartments is much more controversial (1). Among other factors that can influence the complex process of voiding, ageing also has an important negative impact (2).
The aim of the study was to evaluate if there are any anatomical findings that predict voiding disfunction symptoms in women with anterior compartment pelvic organ prolapse. We hypothesized that not only prolapse severity, but also other anatomical findings such as a short genital hiatus or urethral kinking may be associated with voiding disfunction symptoms in these patients.

This was a cross-sectional multicentre study including all women with symptomatic anterior compartment prolapse that were evaluated in the pelvic floor units of two different hospitals between May 2015 and September 2017 prior to surgery. Pelvic organ prolapse was described according to the Pelvic Organ Quantification (POPQ) system. Two gynecologists blinded to symptoms reports performed the examination. Urethral kinking was defined when point Aa was less than + 3 and at least 2 cm higher than point Ba. Obviously, when point Aa reaches maximum descent (+3) kinking is not possible, even if point Ba has greater values. Short genital hiatus was defined at less than 4 cm.
Symptoms of voiding dysfunction were identified using the validated Spanish version of the Pelvic Floor Distress Inventory short form (PFDI-20) (3). Specifically, we used question 5: “Usually experience a feeling of incomplete bladder emptying?” and 6: “Ever have to push up on the bulge in the vaginal area with your fingers to start or complete urination?” that corresponds to questions of the Pelvic Organ Prolapse Distress Inventory (POPDI-6).
Statistical analysis was done by proportion comparison (Chi-square) and multivariate analysis (multiple logistic regression model).

We included 481 patients with symptomatic anterior compartment prolapse scheduled for surgery. Mean age was 63.2 years (SD:9.7; range:37-86) and mean body mass index (BMI) was 29.8 (SD:5.7; range:16.8-70.4). 
Of the total, 269 (55.9%) reported a feeling of incomplete bladder emptying, and 165 (34.3%) indicated the need to push up on the bulge in the vaginal area to start or complete urination in questions 5 and 6 respectively, from the PFDI-20 questionnaire. Prolapse examination in the anterior compartment indicated POPQ stage 2 in 93 (19.3%), stage 3 in 345 (71.7%), stage 4 in 43 (8.9%), and urethral kinking in 173 (36.0%) patients. Maximum urethral descent (point Aa +3) was identified in 86 (17.9%) women. Prolapse examination also identified POPQ stage ≥ 2 in 259 (53.8%) women in the apical compartment, and in 157 (32.6%) in the posterior compartment. A short genital hiatus was identified in 31 (6.4%) women.
The association between different anatomical findings and urinary dysfunction symptoms was adjusted by age as a potential confounder. Voiding dysfunction symptoms were associated with anterior prolapse severity, apical prolapse, urethral kinging and short hiatus, especially when we evaluated the feeling of incomplete bladder emptying (table 1).

As expected, women with larger anterior compartment prolapse were more at risk for voiding dysfunction.  Apical prolapse also had a negative effect on voiding, while posterior prolapse did not. Other anatomical findings that should be considered when evaluating the effect of prolapse on voiding function are urethral kinking and genital hiatus. It seems that urethral kinging was more associated with needing to push up the bulge, while a shorter hiatus increased the risk of incomplete bladder emptying sensation.

In patients with symptomatic anterior compartment prolapse, the severity of this prolapse and the association of an apical prolapse, urethral kinging or a short genital hiatus, increases the risk for voiding dysfunction symptoms.

Dietz HP, Haylen BT, Vancaille TG. Female Pelvic Organ Prolapse and voiding Function. Int Uroginecol 2002; 13: 284-288.
Wagg A, Kung Chen L, Johnson II T, Kirschner-Hermanns R, Kuchel G, Markland A, Murphy C, Orme S, Ostaszkiewicz J, Szonyi G, Wyman J.  Incontinence in frail older person. In Incontinence 6th edition 2017; Pag 1309-1442.
Sánchez-Sánchez B. et al Cultural adaptation and validation of the Pelvic Floor Distress Inventory short form (PFDI-20) and Pelvic Floor Impact Questionnaire short form (PFIQ-7) Spanish versions. Eur J Obstet Gynecol Reprod Biol. 2013;170(1):281-5.